Parkinson's disease is set apart from other neurodegenerative disorders by our knowledge of the key biochemical defect. Dopamine replacement therapy is effective in treating major symptoms of the disease. However, despite the availability of symptomatic therapies, patients experience a functional decline as a result of the progressive nature of the illness. A major unmet need in the treatment of PD is the identification of therapies that slow the rate of progression of neuronal degeneration. Proper investigation of therapies with neuroprotective potential requires infrastructure and collaboration among several sites to evaluate disease modifying effects over several years. The goal of this competing renewal is to report on the contributions of the Institute for Neurodegenerative Disorders (IND) as a clinical center for the NET-PD. IND has played an active role in the recruitment and retention of subjects for LS-1, FS-1 and FS-TOO over the past several years. We enrolled a total of 31 subjects into the program with a retention rate of on average 84%. Our success in our recruitment and retention stems from our relationship with advocacy groups, experience in advertising, a stable and responsive clinical research team and our relationship with the community neurologists in Connecticut who refer, on average, 10 PD patients per month to our research program. As active members of the PD research community, we propose to continue our collaboration with other NET-PD sites, the Central Coordination Center (CCC) and the Statistical Center toward the goal of successfully completing the current trials.